Water Cycle and Water Security - Set 2 Flashcards
1
Q
Natural causes of drought - Short term causes
A
- Blocking anticyclones
- Reduced soil moisture - leads to reduced evaporation
2
Q
Natural causes of drought - Medium term causes
A
- El Nino southern oscillation (ENSO) - reduces rainfall in the western pacific
- Hydrological - reduced amounts of water in rivers or lack of precipitation which reduces amount of snow and therefore snow melt in the summer etc
3
Q
Natural causes of drought - Long term causes
A
- Global atmospheric circulation= Descending air between Hadley and Ferrell cells creates hot and cold deserts
- Climate Change
4
Q
Ecosystem functioning
A
- Biological, Chemical and physical processes that take place within the ecosystem
5
Q
Ecosystem resilience
A
- Capacity of an ecosystem to recover from disturbance or withstand ongoing pressures
6
Q
Wetland
A
Area of land saturated with water, permanently or seasonally - e.g. Everglades in Florida
7
Q
Why are Wetlands important
A
- Act as temporary water store - mitigate river floods downstream
- Act as water filters - trap and recycle nutrients and pollutants
- Support a very diverse food web
8
Q
How has drought affected wetlands
A
- Increased drying = more soil erosion - reduces ability to store water
- Organic soils oxidise - release carbon into the atmosphere
- Nesting sites lost etc = loss of species = gaps in the food chain
9
Q
Why are rain-forests important
A
- 7000 drugs originate e.g. rosy periwinkle from Madagascar which treats Leukaemia
- Attracts tourists
- Prevents soil erosion
- Hardwood timber - used for construction and fuel - UK produced 13 million tonnes in 2014
10
Q
Impacts of drought on forests
A
- takes up to 4 years for forest to recover from drought
- leads to foliage loss, More pests and diseases
- 2000 - 2003 = Severe drought led to significant die off of pinyon pines in USA - 90% died
11
Q
Physical causes of desertification
A
- Less rainfall / drought
- Global warming
- Rivers drying up and less reliability of rainfall = vegetation dies
12
Q
Human causes of Desertification
A
- Livestock numbers increasing = soil depleted of nutrients and land stripped of it’s protective grass cover = vegetation cannot re-establish itself
- Farmers use more land = reduced soil fertility and soil left exposed to wind and rain = vegetation removed
- Increased demand for wood = vegetation removed
13
Q
Water security
A
Capacity of a pop to safeguard sustainable access to adequate quantities of acceptable quality of water for sustainable livelihoods and socio-economic development
14
Q
Water Scarcity
A
Imbalance between demand and supply, classed as physical scarcity or economic scarcity - below 1000m cubed
15
Q
Water stress
A
Country’s water consumption exceeds 10% of it’s renewable freshwater supply, including difficulties in obtaining new quantities of water - below 1700m cubed
16
Q
Where is the world’s water security
A
- Most in Central Asia and the middle east - Least is found in Central Africa and Europe
- Anomaly’s = SE England and southern California face water insecurity
17
Q
How are the worlds water supplies spread unevenly
A
- 60% of water supplies in 10 countries
- 66% of global pop receive only 25% of worlds annual rainfall
18
Q
Water availability gap
A
Imbalance of water usage, with richer countries using up to 10 times more water per head
19
Q
Virtual water
A
- AKA embedded water - embedded in all farm products, food and manufactured goods that are imported
20
Q
Places likely to experience water stress
A
- Pakistan
- Ethiopia
- California
21
Q
Places that are water vulnerable
A
- Spain
- Belgium
- UK
- India
22
Q
Places that have sufficient water supplies - 3000m cubed per person per year
A
- Americas
- Russia
- Scandinavia
- Australia
23
Q
Why is climate change modelling complex and uncertain
A
- Climate dynamics = Way the 4 systems interact with each other is only partially understood
- Global records are incomplete = hard to make future predictions
- Can be difficult to distinguish between the impacts of oscillations e.g. ENSO and Climate change
24
Q
How can climate warming lead to an increase in precipitation
A
Increased evaporation and increase in atmospheric water holding capacity = more moisture content in the atmosphere = enhanced precipitation rates
25
Future trends in drought
- Moisture holding capacity of the atmosphere increasing at 7% per 1 degree warming
- Leads to more flooding
26
Climate change effects on - Snow pacts
- Amount of snow collecting and surviving is decreasing as air temps increase
27
Climate change effects on - Glacier mass
- Most are in retreat - those in Antarctica are thinning as ice shelves on the warmer sea melt and break up
28
Climate change effects on - Lakes and reservoirs
Higher evaporation rates form open water sources due to warmer temps - lower precipitation also means they are not refilled increasing the risk of drought
29
Climate change effects on - Permafrost
Tundra's experiencing the greatest degree of warming - all permafrost is melting
30
Climate change effects on - Soil moisture
Great contrast around the world - Higher air temps draw more water from soils by evaporation
31
Stream flow
Heavy precipitation, high humidity or snow and ice melt lead to more water running off the surface and entering the streams - increasing the flood risks
32
Future flood frequency
- South Asia has the highest risk as well as central Africa and South AMERICA
- Biggest decrease in Scandinavia and central Europe
33
Physical causes of water insecurity
- Climate variability = influences global distribution of water - Varey's as result of atmospheric pressure systems
- Saltwater encroachment = Sediment layers that make up the coast provide pathways for saltwater intrusion
34
Human Causes of water insecurity
- Saltwater encroachment = Increased pumping of groundwater in 1900s - also barriers from 1950s not effective
- Over abstraction - agriculture uses 2/3 of water - removal of freshwater on coasts can upset natural balance and lead to saltwater intrusion
- Water contamination - Chemical fertilisers leads to eutrophication which makes the water contaminated
- Industrial water pollution - in China 390 million people use contaminated water daily
35
Pressure on finite freshwater resources
- Increasing pop - 55% increased demand from 2015-2050
- Farming
- Economic development - global GDP increases 3.5% annually
- Better living standards
36
How many people lack access to clean water
1 billion
37
Physical water security
Determine by...
- Climate change - can lead to the development of deserts
- Topography
38
Price of water
- Physical costs - Water can ne transported long distances e.g. LA
- Degree of demand = high prices during 2015 Californian drought
- Insufficient infrastructure = Those living in slums rely on water tankers etc - bottled water can be 4 time more expensive than tap water
39
Importance of water
- Health - clean water helps avoid diseases
- Human rights - Improves social dignity
- Food
- Ecosystems
- Cleanliness
40
Causes of water related diseases
- Lack of sanitation = 10% of global disease burden
- Water = breeding ground for diseases such as parasitic worms
41
3 aims of water aid
- clean water
- proper toilets
- Good hygiene
42
Water and economic development
- Energy production - dams can exaggerate effects of drought downstream
- Manufacturing - used in cooling = cost of goods rise
- Investment and development water availability aids investment into an area
- Agriculture
- Control pollution
43
Industrial and energy use of water
- 20% freshwater extraction is for energy production
- Industry contaminates rivers and groundwater
- Water used for HEP is returned to source unchanged - although warmth can impact on ecosystems
- Biofuels = production of 1 litre of bioethanol uses 10,000 litres of water
44
Green revolution
1/5 of worlds land is under full irrigation
- Green revolution increased food security causing environmental concerns
- Takes 2975 litres to produce 1kg of Rice
45
Water security and potential for water conflict - Interesting facts
- 2/3 of conflicts from 1948-2008 were over water
- Many military threats regarding the destruction of dams and cutting off of water supplies
- 90% of countries share water basins with neighbours
46
Water conflicts within England
- Building a dam in Kielder - concerns over flooding of farms and villages
- Some reservoirs have not been built due to NIMBY-ism = Not in my back yard protests
47
Managing water supplies using hard engineering - Mega dams
- Have ability to store 15% of annual global run-off
-- Pros of the 3 gorges dam --
- Surplus water sent to Northern China
- Electricity generated is vital for Chinas growth
-- Cons of the 3 gorges dam --
- 632 km squared has been flooded - 1.3mn had to be relocated
- Water quality is low as waste from industry enters from upstream
- Dams are back in fashion as less developed have more room on rivers to build them - developed countries are too built up
48
Managing water supplies using hard engineering - Desalination
- Breakthroughs in technology have made it more cost effective
- Top nations that use this method are...
- Saudi Arabia
- USA
- UAE
-- Pros --
- More viable than other hard engineering water transfers
-- Cons --
- Dumped salt can damage coral reefs
- Saudi etc use fossil fuels to run the plants
49
# 3 A's
Water should be
Available
Accessible
Affordable
50
4 features of the water sustainability quadrant
- Futurity - ensuring security of supplies for the future
- Environment - restoration of damaged water supplies
- Public participation - decentralised decision making
- Equity and social Justice - ensures supplies are secure and at an affordable price
51
Drip irrigation schemes
- sensors measure crop temps - reduce water usage however the technology is expensive and thus not available too may farmers
52
Magic stones
- Practiced widely across the semi arid Sahel region - stones used to stop rainwater flowing downhill
- Pros = Cheap and accessible to all
- Cons = Requires rain and so doesn't work in times of drought
53
GM crops
- Bread so they are more tolerable to diseases and drought
- Pros = More crops are able to be produced
- Cons = Worries for peoples health
54
Hydroponics
- Crops grown in mineral nutrient solutions - grown in greenhouses which are CO2 and temp controlled
- Pros = sustainable in terms of water
- Cons = requires lot's of energy
55
Recycling water
- Dongtan, China - eco friendly city = 2 water pipes going into houses - Grey water = rain - used for toilet etc and then one for drinking water
- Pros = Less use of clean piped water = lower costs
- Cons = Reliant on rainwater and small scale
56
Water metres
- Instillation of smart metres which monitor water usage
- Pros = makes people more aware of consumption and helps plan for future
57
Irrigated water resource management (IWRM)
Promotes the coordinated development of management of water, land and related resources in order to maximise economic and social welfare
58
Main features of IWRM
- Freedom from corruption
- Environmental protection
- Food and water security
- Decentralising of decision making = good governance
59
Management of water resources
- Groundwater management
- Waterway management
- Integrated urban water
- Monitoring technology
